Of note, similar observations were described for other SMA-related biomarker studies: a biomarker study on 16 adults with SMA type 3 and 4 under Nusinersen treatment over 22 months reported on a significant decrease of pNF-H and increase of Chitotriosidase-1 (CHIT1) in CSF upon treatment but no correlation of this molecular change with clinical outcome measures. This evidence concerns the gene CHIT1 and proximal spinal muscular atrophy.